Isothermal Crack Healing and Strength Recovery in UO2 Subjected to Varying Degrees of Thermal Shock

Abstract
Isothermal crack healing and strength recovery were investigated in UO2 pellets subjected to varying degrees of thermal shock by water quenching. It is shown, as was speculated in an earlier paper, that crack density and/or crack width in the specimen strongly influence the subsequent healing behavior. Experimental data were used to demonstrate that, under the present thermal shock conditions, the time required for complete healing increased exponentially with the number of cracks/unit length of the specimen.